Soft x-ray reflection from silicon and quartz mirrors.

The optical constants of silicon and quartz in the soft x-ray region (400-3750 eV) determined from the incidence-angle dependence of the specular reflectance are reported. The measured reflectance-vs-angle of incidence curves for the lower energies are quantitatively explained using a simple diffractive scattering model including the interference effect between the reflected beams, while those for the higher energies can be interpreted in terms of the microfacet model without the interference effect.